1. Field of the Invention
The present invention relates to a surgical instrument or use in minimally invasive surgical techniques.
2. Description of the Related Art
Minimally invasive surgery lowers morbidity rates and shortens recovery periods and thus also causes substantially lower process and overall treatment costs for a patient compared to open surgery. Most recent developments in the field of minimally invasive surgery have been directed to instruments for complex operations such as, for example, in cardiosurgery, thereby reducing the risks and strains for the patient even in complex operations and reducing costs for private and legal insurances. It is expected that the spectrum of applications of the minimally invasive surgical technique shall not only be extended but also that the instruments used for this purpose shall additionally become cheaper despite the ever more improved surgical techniques.
U.S. Pat. No. 5,254,130 discloses a surgical device for minimally invasive surgery including a tubular or shank-like housing having an axially extending shank bore. A first oblong part includes an elastic preshaped, i.e., curved, material which extends through the shank bore and includes a proximal end and a distal end. When the distal end is extended out of the longitudinal bore, it adopts a first shape corresponding to the preshaping, i.e., the curve. When the distal end is retracted back into the bore, it adopts a second shape corresponding to the shape of the shank bore, i.e., the first part straightens when it is retracted into the bore.
A second oblong part, which also has a proximal end and distal end, is linked to the first part at a parallel distance therefrom. The second part is bent by the first part, when the first part changes from its first to its second shape and vice versa. In addition, the second part is held relatively rotatably about the axis of the first part.
A working head or mouth member is arranged at the distal end of the second oblong part. The working head or mouth member moves along with the second part during the bending or curving movements of the latter and is rotatable about the axis of the first part by the second part. This configuration enables an operator to move the head of the surgical device for instance along a path curved in a plane and then to rotate the working head in a different dimension, for instance about the axis defined by the direction of the curved path.